Linux Command

tee
Function: Read from standard input and write to both standard output and files
Usage: tee [OPTION]... [FILE]...
df
Function: report file system disk space usage
Usage: df [OPTION]... [FILE]...
fuser
Function: identify processes using files or sockets
Usage: fuser [-a|-s|-c] [-4|-6] [-n space ] [-k [-i] [-signal ] ] [-muvf] name ...
tac
Function: concatenate and print files in reverse
Usage: tac [OPTION]... [FILE]...
echo
Function: display a line of text
Usage: echo [SHORT-OPTION]... [STRING]...
sort
Function: sort lines of text files
Usage: sort [OPTION]... --files0-from=F
tput
Function: initialize a terminal or query terminfo database
Usage: tput [-Ttype] capname [parms ... ]
date
Function: print or set the system date and time
Usage: date [OPTION]... [+FORMAT]
dd
Function: convert and copy a file
Usage: dd [OPERAND]...
write
Function: send a message to another user
Usage: write user [ttyname]
chown
Function: change file owner and group
Usage: chown [OPTION]... --reference=RFILE FILE...
mv
Function: move (rename) files
Usage: mv [OPTION]... [-T] SOURCE DEST
logname
Function: print user's login name
Usage: logname [OPTION]
test
Function: check file types and compare values
Usage: test EXPRESSION
man
Function: format and display the on-line manual pages
Usage: man [-acdDfFhkKtvVwW] [--path] [-m system] [-p string] [-C config_file] [-M pathlist] [-P pager] [-B browser] [-H htmlpager] [-S section_list]